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The presence of coal and coal-bearing rocks in waste rock dumps of open-pit coal mines contributes to the occurrence of spontaneous combustions that negatively affect the environment and people. Measurements of the temperature and the content of hazardous gases in the temperature anomaly that arose in the waste rock dump of the open-pit coal mine were made to assess the parameters of spontaneous fire seats. In the course of the study, the efficiency of detecting spontaneous fire seats in waste rock dumps was assessed by measuring the rock temperature in the wells with a depth of 2.5 m, drilled at a distance of 20 m from each other. The experiment showed the difficulty of drilling control wells in waste rock dumps and the impossibility of drilling them on the slopes of dumps, especially in spontaneous fire seats with a high rock temperature. The necessity of casing control wells with pipes makes it difficult to measure the rock temperature at different depths. It was found that there are sharp drops in the rock temperature in the heated area of the dump, which cannot be detected when the wells are located at the recommended distance. The measurements showed that in all wells the temperature increases with depth, therefore the depth of wells recommended by the regulatory documents does not allow determining the size of the heated area.

The need to use hydraulic technology for washing out quaternary bedrock, as well as heterogeneous rocks previously piled in hydraulic-mine dumps located above commercial coal reserves, requires the use of modern high-performance equipment. As such equipment, it is advisable to use the new GD-300 hydraulic mining giants – monitors, which are designed, manufactured and tested at Kuzbass open pits. In order to increase the performance of hydraulic monitors at Kuzbass open pits, the following dependencies are determined in the article: changes in the amount of water flow through the hydraulic monitors on the nozzle diameter and the pressure in front of it; changes in the amount of solid rock washed out by the hydraulic monitor ‒ solid flow on the nozzle diameter at various values of the pressure in front of it; changes in the solid flow on the pressure in front of the nozzle.

At present, there are no standard methods for assessing seismic safety of underground mines during blasting on the earth’s surface. The need for such assessments arises when underground mines are located near open-pit coal mines, when the mine fields development is continued into the open pit, and when open surface coal mines use highwall miners. The issues of assessing seismic safety can be complicated by the lack of experimental data on vibration parameters, for example, if the answer is already required at the stage of new mines designing. The paper also provides an analysis of experimental data, including the results of monitoring the state of underground mines during seismic impacts of varying degrees of intensity. It is shown that the spread of the observed PPV, at which local damage or deformation of the underground mines has taken place, attains high values. In the absence of such data for underground mines in specific mining and geological conditions, it is recommended that the maximum allowable PPV vпр be assigned taking into account the class of underground mines and the type of support. At the same time, it is noted that the recommended vпр values given in the literature relate to the openings that were driven in the solid without geological disturbances and anomalies; not deviating from regulatory requirements regarding the state of workings; in the absence of danger of groundwater breakthrough; in the absence of danger of gas-dynamic phenomena, and other negative factors. If this is not the case, according to the requirements of the Federal norms and rules of industrial safety, the seismic safety distance should be increased by 2 times. This requirement is equivalent to multiplying the maximum permissible vibration velocity by a decreasing coefficient k=2b, where the power of two is the regression parameter b obtained from the experimental data processing.